Whereas the PRI is planning to field Beatriz Paredes, a well-known figure with close ties to her party's machine in the capital, the PRD has struggled to unite behind a strong candidate.

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During first minister's question time Mr Salmond said Scotland's two largest parties should unite to demand new borrowing powers, capital acceleration and Olympic 2012 consequentials, which he said were denied by the last Westminster administration.

BBC: First minister's questions

Unite, the union representing bus workers, said they were the only transport workers in the capital who had not received an Olympics bonus.

BBC: Heathrow Express staff get ?700 Olympic pay deal